If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
Finish the solution so that it returns the sum of all the multiples of 3 or 5 below the number passed in.

Note: If the number is a multiple of both 3 and 5, only count it once.

def solution(number):

Solution:
```python
def solution(number):
    sum = 0
    for i in range(number):
        if i%3==0 or i%5==0:
            sum = sum + i
    return sum